When Angel Pagan discussed the small tear in his left hamstring tendon over the weekend, he said that he would miss about six weeks if the injury required surgery. It turns out that he’ll have to miss significantly more time.

Giants manager Bruce Bochy told Andrew Baggarly of CSNBayArea.com that Pagan will undergo surgery tomorrow and is expected to miss 12 weeks. In other words, he’s at risk for missing the rest of the regular season. That’s a tough blow for the defending World Series champions.

Bochy plans to roll with Gregor Blanco as his primary center fielder and leadoff man while Pagan is sidelined, though Andres Torres and Juan Perez also figure to see playing time there. There’s still about five weeks until the trade deadline, so the Giants still have time to look for potential upgrades in the outfield.

Losing him is a big one. He is kind of their spark plug. He’s able to play center and run the bases and hits pretty decent. But sometimes a loss in the dugout/clubhouse can be just as bad. Their pitching woes seem to be the most glaring problem though. The Giants are pretty lucky that they play in the N.L. West where their are no run away horses pulling away. But the division is still good enough to keep them down and out unless they can find some consistency and finally put some form of a decent everyday healthy team on the field. The Cards, Reds’s, Braves, and a few other teams are no easy obstacles in the Giants way. To go along with the improved Dodgers…(if they can stay healthy also), and Diamondbacks and Rockies. It still starts and ends with…pitching – pitching – pitching…